PORTLAND, Maine — Authorities say 47 passengers had to be evacuated from a plane at Portland International Jetport after the crew reported smoke in the cockpit.

No one was hurt when the Chicago-bound United flight was emptied shortly after boarding at about 6:45 p.m. Monday.

The crew reported a haze in the cockpit and a burning smell, but the exact cause was not immediately clear.

A Portland Fire Department official said the smoke was likely caused by a short circuit.

The jetport’s air rescue team responded, but could not find any evidence of a fire inside the plane, which was taken out of service.

Some passengers were able to find other flights to Chicago on Monday night while many passengers had to stay overnight in Maine.